Meet Kepler For The Masses

Only an elite few have had pockets deep enough to lay claim to NVIDIA's high-end Kepler GPUs, until now. The arrival of the GTX 660 means big things for those wanting a powerhouse GPU in the sub $300 price range. Starting at $229, the GTX 660 is classified as a mid-range offering in the Kepler lineup. Thanks to the 960 CUDA cores, three graphics processing clusters, 80 texture units, and 192-bit memory interface found on the GK106 chip that powers the GTX 660, gamers can expect up to four times the frame rates as NVIDIA's 8800 GT along with higher detail thanks to DirectX 11. Given that 40% of gamers are using a GPU with DirectX 10 or older, the GTX 660's DirectX 11 capability is a major point of marketing for NVIDIA. Other drool-worthy technologies within the reach of the GTX 660 include NVIDIA PhysX, Adaptive VSync, GPU Boost, and TXAA Anti-Aliasing.

Two of the most popular cards used by gamers today, the GTX 460 and GTX 560Ti, sat at the same price-point as the new GTX 660. The GTX 660 is NVIDIA'S new card which rules the bang-for-your-buck segment, offering very high gaming performance at a price point that is attainable by just about anyone who is hungry for an upgrade. NVIDIA is excited to finally bring an affordable Kepler chip to market because there is a large number of gamers who are primed to upgrade to a current-gen card. If they are anything like I was before I started reviewing hardware, I was an every-other-gen upgrader. Nvidia sees that there are droves of gamers rocking GTX 460s and even a few generations back, with 9800GTs and GTX 260s, who will finally see big enough gains to make the jump to a new card.

Microsoft DirectX 11

A discussion of DX11 really boils down to two things: tessellation and displacement mapping. Put simply, a displacement map stores height information to give texture to surfaces it is applied to. Limitations arise from a lack of vertices to depict complex textures. Tessellation is able to slice and dice the polygons to deliver highly textured characters that border on film-like realism. Given that tesselation is programmable in DirectX 11, challenging graphics problems like bump mapping, smoothing, object popping, and artwork scaling. This means in a nutshell that gamers will enjoy all the details of their favorite games both far away and close up. A more detailed explanation of DX11 tessellation can be found on the GeForce website.

NVIDIA PhysX

Until we acheive something akin to the Star Trek holodeck, gamers will continue to demand a higher sense of realism from their virtual environments. Flags that don't flutter from a gust and walls that don't crumble from a shotgun blast are dead giveaways of a faked world. PhysX represent NVIDIA's best effort to pull the wool over our eyes by providing environments, objects, and figures that respond dynamically to the actions of the player and the game's AI.

NVIDIA Adaptive VSync

Vertical Synchronization, or VSync, is a known prescription for screen-tearing when an application's frame rates exceed the refresh rate of your monitor. We all know there's no such thing as a free lunch, and previous users of VSync suffered from stuttering due to the locked frame rate. Just as it sounds, Adaptive Vsync can selectively enable and disable the VSync frame rate lock, eliminating any sharp dips in performance while still preventing screen-tearing.

GPU Boost

Graphics cards are designed to operate under a specific wattage called the Thermal Design Point (TDP). However, a great number of popular games consume a fraction of the TDP rating, leaving a great amount potential untapped. GPU Boost dynamically alters the clock speed of the GPU based upon the app that is currently running to extract every necessary watt without going over the TDP threshhold. All this is accomplished via realtime hardware monitoring, so there's no need for applicaiton profiles or updated drivers when the latest great title hits the shelves. One thing that overclockers need to keep in mind is that due to the presence of GPU Boost, their graphics card has two effective clock speeds, a base clock and a boost clock. This gives us a frequency envelope of what the GPU will typically run at (the boost clock) and the lowest speed we'll see (the base clock). Thus there are two approaches to overclocking a card equipped with GPU Boost, increasing the base clock speed to induce a higher corresponding Boost clock, or manually increasing the target power level.

TXAA Anti-Aliasing

Anti-aliasing is particularly important for makers of CG films and game engines to ensure that the audience isn't distracted by jagged edges. Sophisticated filters enable to TXAA work to smooth these edges out at a level comparable to 4x the previous generation MSAA Anti-Aliasing. You also won't notice any jagged lines crawling in front of a slow-moving camera thanks to TXAA taking a "jitter" sample.

A Historic Comparison

The GeForce 8800 GT and 9800 GT are the GTX 660's closest ancestors and they both sold like hotcakes after their respective releases. Being that they retailed for $199 and $249 respectively, these graphics cards straddle the cost of today's GTX 660 and offered great bang for the buck in their time. It comes as no surprise that this current gen mid-range GeForce card blows its older relatives out of the water by offering twice the memory bandwidth and 8x the number of CUDA cores thanks to a removed shader clock. Up to 4x the frame buffer and over 2x texture fill rate performance makes this upgrade even more compelling for those who want to get the most from their 1080p gaming.

If we move our comparison to more recent years, the GTX 460 and GTX 560 Ti come into the picture. Both follow the same theme of cost-effective performance as the GTX 660 and both can boast of having DirectX 11 and PhysX under their belts. While it’s difficult to directly compare these cards due to their varying architectures, the relative performance between them is evidence of the GTX 660’s dominance. According to NVIDIA’s own 3DMark Vantage tests, the GTX 660, 560, and 460 score 30000, 20500, and 15500 respectively. That represents a 46% advantage over the GTX 560 Ti and an amazing 94% improvement over the GTX 460, both of which hold their own in current-gen games. If you want to best the GTX 660 with a previous gen, you’ll need to have ownership of a GTX 580 or higher, something that simply isn't cost effective, or frankly, makes much sense.